package com.xiaolun.reversepolishcal;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Stack;
import java.util.regex.Pattern;

/**
 * @time: 2020-09-26 10:37
 * @author: likunlun
 * @description: 1
 */
public class ReversePolishMultiCalc2 {
	/**
	 * ƥ� + - * / ( ) �����
	 */
	static final String SYMBOL = "\\+|-|\\*|/|\\(|\\)";

	static final String LEFT = "(";
	static final String RIGHT = ")";
	static final String ADD = "+";
	static final String MINUS= "-";
	static final String TIMES = "*";
	static final String DIVISION = "/";

	/**
	 * �Ӝp + -
	 */
	static final int LEVEL_01 = 1;
	/**
	 * �˳� * /
	 */
	static final int LEVEL_02 = 2;

	/**
	 * ����
	 */
	static final int LEVEL_HIGH = Integer.MAX_VALUE;


	static Stack<String> stack = new Stack<>();
	static List<String> data = Collections.synchronizedList(new ArrayList<String>());

	/**
	 * ȥ�����пհ׷�
	 * @param s
	 * @return
	 */
	public static String replaceAllBlank(String s ){
		// \\s+ ƥ���κοհ��ַ��������ո��Ʊ������ҳ���ȵ�, �ȼ���[ \f\n\r\t\v]
		return s.replaceAll("\\s+","");
	}

	/**
	 * �ж��ǲ������� int double long float
	 * @param s
	 * @return
	 */
	public static boolean isNumber(String s){
		Pattern pattern = Pattern.compile("^[-\\+]?[.\\d]*$");
		return pattern.matcher(s).matches();
	}

	/**
	 * �ж��ǲ��������
	 * @param s
	 * @return
	 */
	public static boolean isSymbol(String s){
		return s.matches(SYMBOL);
	}

	/**
	 * ƥ������ȼ�
	 * @param s
	 * @return
	 */
	public static int calcLevel(String s){
		if("+".equals(s) || "-".equals(s)){
			return LEVEL_01;
		} else if("*".equals(s) || "/".equals(s)){
			return LEVEL_02;
		}
		return LEVEL_HIGH;
	}

	/**
	 * ƥ��
	 * @param s
	 * @throws Exception
	 */
	public static List<String> doMatch (String s) throws Exception{
		if(s == null || "".equals(s.trim())) throw new RuntimeException("data is empty");
		if(!isNumber(s.charAt(0)+"")) throw new RuntimeException("data illeagle,start not with a number");

		s = replaceAllBlank(s);

		String each;
		int start = 0;

		for (int i = 0; i < s.length(); i++) {
			if(isSymbol(s.charAt(i)+"")){
				each = s.charAt(i)+"";
				//ջΪ�գ�(������������ ���������ȼ�����ջ�����ȼ� && ���������ȼ�����( )�����ȼ� ���� ) ����ֱ����ջ
				if(stack.isEmpty() || LEFT.equals(each)
						|| ((calcLevel(each) > calcLevel(stack.peek())) && calcLevel(each) < LEVEL_HIGH)){
					stack.push(each);
				}else if( !stack.isEmpty() && calcLevel(each) <= calcLevel(stack.peek())){
					//ջ�ǿգ����������ȼ�С�ڵ���ջ�����ȼ�ʱ��ջ���У�ֱ��ջΪ�գ�����������(������������ջ
					while (!stack.isEmpty() && calcLevel(each) <= calcLevel(stack.peek()) ){
						if(calcLevel(stack.peek()) == LEVEL_HIGH){
							break;
						}
						data.add(stack.pop());
					}
					stack.push(each);
				}else if(RIGHT.equals(each)){
					// ) �����������γ�ջ����ֱ����ջ���������˵�һ��)����������ʱ)��ջ
					while (!stack.isEmpty() && LEVEL_HIGH >= calcLevel(stack.peek())){
						if(LEVEL_HIGH == calcLevel(stack.peek())){
							stack.pop();
							break;
						}
						data.add(stack.pop());
					}
				}
				start = i ;    //ǰһ���������λ��
			}else if( i == s.length()-1 || isSymbol(s.charAt(i+1)+"") ){
				each = start == 0 ? s.substring(start,i+1) : s.substring(start+1,i+1);
				if(isNumber(each)) {
					data.add(each);
					continue;
				}
				throw new RuntimeException("data not match number");
			}
		}
		//���ջ�ﻹ��Ԫ�أ���ʱԪ����Ҫ���γ�ջ���У���������ջ��ʣ��ջ��Ϊ/��ջ��Ϊ+��Ӧ�����γ�ջ���У�����ֱ�ӷ�ת����stack ��ӵ�����
		Collections.reverse(stack);
		data.addAll(new ArrayList<>(stack));

		System.out.println(data);
		return data;
	}

	/**
	 * ������
	 * @param list
	 * @return
	 */
	public static Double doCalc(List<String> list){
		Double d = 0d;
		if(list == null || list.isEmpty()){
			return null;
		}
		if (list.size() == 1){
			System.out.println(list);
			d = Double.valueOf(list.get(0));
			return d;
		}
		ArrayList<String> list1 = new ArrayList<>();
		for (int i = 0; i < list.size(); i++) {
			list1.add(list.get(i));
			if(isSymbol(list.get(i))){
				Double d1 = doTheMath(list.get(i - 2), list.get(i - 1), list.get(i));
				list1.remove(i);
				list1.remove(i-1);
				list1.set(i-2,d1+"");
				list1.addAll(list.subList(i+1,list.size()));
				break;
			}
		}
		doCalc(list1);
		return d;
	}

	/**
	 * ����
	 * @param s1
	 * @param s2
	 * @param symbol
	 * @return
	 */
	public static Double doTheMath(String s1,String s2,String symbol){
		Double result ;
		switch (symbol){
			case ADD : result = Double.valueOf(s1) + Double.valueOf(s2); break;
			case MINUS : result = Double.valueOf(s1) - Double.valueOf(s2); break;
			case TIMES : result = Double.valueOf(s1) * Double.valueOf(s2); break;
			case DIVISION : result = Double.valueOf(s1) / Double.valueOf(s2); break;
			default : result = null;
		}
		return result;

	}

	public static void main(String[] args) {
		//String math = "9+(3-1)*3+10/2";
		String math = "12.8 + (2 - 3.55)*4+10/5.0";
		try {
			doCalc(doMatch(math));
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}
